We will continue to study the gross pathology of the congenitally abnormal hearts sent to us by the pathologists of New Jersey, Eastern Pennsylvania and other parts of the country. At the microscopic level, we will study the difference between the hemodynamically altered valve and the dysplastic valve. Our emphasis in congenital heart disease will be the cause of sudden death long after surgery. We will computerize our data on our collection of more than 5500 contenitally abnormal hearts. This will form the basis of a book on congenital heart disease. We are in the preliminary stage of establishing an epidemiologic project in congenital heart disease for New Jersey and Eastern Pennsylvania area. In the conduction system, we will continue to study the anatomic base of the Wolff-Parkinson-White Syndrome, and other arrhythmias. We will continue to study the conduction system and the entire heart in sudden death in the younger age group who apparently were living a normal life. We will study the comparative usefulness of the Imatron, echocardiography and angiocrdiography in the clinical diagnosis of congenital heart disease. We will try to discover new methods of imaging in the use of the Imatron. In ablative procedures, in the conduction system, we will study histologically the comparative effects of electric shock and radio frequency energy on the conduction system. We will collaborate wth Dr. Leonard Dreifus in his work on the nervous control of the pre-AV nodal and AV nodal areas in the rabbit. The methodology to be used is the study of congenitally abnormal hearts qualitatively and quantitatively as described by Lev and Bharati and the study of the conduction system is by methods of Lev and Bharati. Our work, in addition to giving an anatomic base for various types of arrhythmias and sudden death, may in the long run help in the creation of an animal model for these arrhythmias and sudden death, and help in their eradication. Our epidemiologic work may help in indicating the role of irradiation, drugs, and industrious waste in the causation of congenital heart disease in the Delaware Valley.